When you can't use a database, what do you use?

I am working on a project that should be powered by a database. The data changes frequently, the items are displayed on the website based on start / end dates, and the user needs to be able to filter it in real time based on category. I do not have access to the company database nor do I have permission to create a new database. I do have the ability to upload files and modify the HTML in the CMS, so I am currently using XML & JavaScript/jQuery to power the website. The business provides an excel file with the data which I have programmed to spit out the xml code. Due to the large number of items I had to break the XML into 2 separate files or else it would crash IE8 (which unfortunately I am required to support) and it's kind of slow on modern browsers. As if that wasn't bad enough, the XML and JS files take 1-2 hours to go live on the akamai server so I have built-in methods to add/remove/update items (there are often changes that need to go live immediately). Whenever something changes, I go into the CMS and call those methods using inline JavaScript. Oh and did I mention that the CMS will not accept HTML data attributes? So filtering based on data attributes is out. All of this works, but it sucks. Is there a better way to do this?